mastaGRID Composite for New M5 Arncliffe Compound
The WestConnex New M5 is proposed to more than double the capacity of the M5 East Motorway corridor by providing new twin tunnels from Kingsgrove to St Peters. A joint venture comprising CPB, Dragados and Samsung C&T is delivering this project.
Supporting the main New M5 project is a permanent operational facility in Arncliffe. A range of infrastructure was to be built on the Arncliffe site, including a ventilation facility, emergency smoke extraction facility, substation power supply, water treatment facility plus a parking area for staff.
The water treatment facility will process construction wastewater as well as groundwater collected around the tunnels, where it will be treated to the quality required by Sydney Water. The ventilation facility has been designed to meet stringent air quality standards, coupled with aviation requirements, as it sits close to the main flight path of Sydney Airport.
The intended site for these structures is located on government-owned land that is currently occupied by the Kogarah Golf Course.
With the existing soil more suited to golfing than supporting industrial infrastructure, the engineering team required a reliable, high-quality geogrid reinforcement to strengthen and stabilise the soil, ready for construction of the compound.
GEOmasta was contracted for supply and delivery of the geogrid required for the base stabilisation. Three layers of mastaGRID Composite Geogrid were laid as both separation and stabilisation layers. This created a platform that could be used as the New M5 tunnel entry and exit point.
mastaGRID Composite geogrid reinforcement is manufactured from polypropylene through the process of extruding, longitudinal and transverse heat stretching. It is then heat bonded to the grid to form a sound composite structure.
It is designed to prevent reflection cracking, water damage and improve load capacity in road construction and renovation. It has high-temperature resistance and anti-fatigue properties, therefore extending the life of asphalt pavements.
At the completion of construction, operational facilities will be permanently located on a small part of the site to support the New M5 motorway tunnels.
Construction of the New M5 began in mid 2016 and is due to be completed by late 2019.